Metal lath



C. R. BIRDSEY METAL LATH Oct. 16, 1934.

Filed Dec. 28, 1928 I I l INVENTOR CHF/EL E6 E. BIRD-SE)- ATTORN Patented Oct. 16, 1934 METAL LATH Charles R. Birdsey, Hinsdale, 111., .assignor to United States Gypsum Company, Chicago, Ill., a

corporation of Illinois Application December 28, 1928, Serial No. 328,872

2 Claims.

This invention relates to a metal lath and has reference more particularly to a metal lath possessing utility as a supporting and reinforcing member for cementitious material used for parti- 5., tions, floors and roofs.

For metal lath used for roofs in which the metal lath spans the space between purlins and sub-purlins, it is desirable to have the metal as stiif and rigid as possible so that no deflection I will occur with long spans between purlins when the cementitious material is poured onto the lath and later when workmen walk over the roof. Some types of metal .lath are not reversible so that a certain amount of care is necessary in applying the lath to its supporting members to insure that the correct face is outward. With certain types of metal lath in which corrugations or ribs are spaced apart by expanded metal, the strands of the expanded section are stretched or .3 elongated during the expanding process, with the result that the stiffness of the finished article is reduced below that which would occur if no stretching of the metal of the strands took place.

An object of this invention, therefore, is to pro- 2 vide a metal lath having a maximum amount of rigidity and stiffness so that fewer purlins will be required for supporting same.

Another object of the invention is to provide a metal lath which is reversible so as to reduce the amount of care necessary in the application of the metal lath to its supporting members.

A further object of the invention is to provide a metal lath in which no stretching of the flat metal beween the ribs occurs.

A still further object of the invention is to provide a metal lath on which the rough edges produced by slotting and flanging are all positioned below the plane of the metal lath so that injury to workmen will be minimized; also to improve metal lath in other respects hereinafter specified and claimed.

Reference is to be had to the accompanying drawing forming a part of this specification, in which Fig. 1 is a perspective view of my improved metal lath,

Fig. 2 is a transverse sectional view through the metal lath,

Fig. 3 is a fragmentary plan view of my metal 0.. lath applied to a wall or roof,

Fig. 4 is a transverse sectional view through the device as shown in Fig. 3, and

Fig. 5 is a transverse sectional View of a modifled form of my metal lath in nested position.

The metal lath consists principally of a sheet (Cl. 72-116) I of metal, such as steel, formed with a plurality of ribs or flanges extending at right angles to the plane of connecting sections 11, so that said ribs form Z-bars with the connecting section. It will be seen from Fig. 1 that each of the sections 11 is provided with a series of slotted openings 12, which are preferably Wedge shaped, and are formed by first making a straight out in the metal and then forcing the edges of the cut outwardly from the plane of the metal to form stiffening flanges 13. These flanges 13 are preferably arcuate, and concavo-convex in cross section (see Figs. 1, 2 and 5). The slots 12 are preferably formed parallel with the grain of the metal and separated by substantially equi-distant .9 reticulations, so that a maximum stiffness is obtained. It will be seen that the flanges 13 of one section extend in the opposite direction to the similar flanges on the adjoining sections and the sharp edges of the flanges 13 in one section are below the plane of the metal in the adjoining section so that the workman is more or less protected from injury from such sharp edges by the face of the adjoining section.

One of the important advantages of my improved metal lath is that the flanges are in opposed relation on adjacent surface whereby the lath is reversible, or alike on both sides, so that unskilled labor may be used to apply the metal lath to supporting beams is without danger of incorrect application. Wires 15 may be passed through the slots 12 and around the beams 14 in order to secure the metal lath in position on said beams. After application to the beams, cementitious material 16 may be applied to the metal 0 lath in the usual way by plasterers tools. The beams 14 may be of metal of any desired structural shape, or wooden beams 17 may be used in which case, the metal lath may be attached to said beams by nails 18.

In the modified form of the invention shown in Fig. 5, the ribs 10A are inclined at an angle less than to the plane of the section 1l-A so that during shipment the metal lath may be nested together. The slots 12-A may also be $0 arranged to register one with the other and assist in the nesting operation.

I would state in conclusion that while the examples illustrated constitute a practical embodiment of my invention, 1 do not wish to limit 10 5 myself to these precise details since manifestly the same can be considerably Varied without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, I claim ll! as new and desire to secure by Letters Patent:--

1. A metal lath comprising alternate, flat sections connected by integral, angular ribs, each section being provided with a series of perforations comprising straight cuts without connecting transverse outs and extending longitudinally only of the grain of the metal, said perforations having outwardly pressed, stiffening flanges formed along the edges of said perforations, the flanges of one section being similar to and extending in the opposite direction to those of the adjoining section so as to form a reversible structure.

2. A reticulated metal lath comprising a plurality of interconnected reversible flat sections in different planes, integral flat members at an angle to said sections and connecting the sections of each plane, each of said sections being provided solely with a plurality of unconnected straight cuts to provide bonding slots in said lath, said cuts extending substantially parallel with the grain of the metal, and the edges of the cuts being forced outwardly from the plane of the sheet to form opposed arcuate stiffening flanges, concave-convex in cross-section, said flanges extending in opposite directions in adjacent sections so as to impart reversibility to the metal lath and so that the faces of said lath are substantially alike.

CHARLES R. BIRDSEY.

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